WASHINGTON -- Senate Democrats who were previously opposed to changing filibuster rules via the "nuclear option" are so fed up with GOP obstruction of the president's nominees that they now say they want to go nuclear.

"I am very open to changing the rules for nominees," Sen. Barbara Boxer (D-Calif.) told The Huffington Post. "I was not before, because I felt we could work with them. But it's gotten to an extreme situation where really qualified people can't get an up-or-down vote."

"I do now," Sen. Dianne Feinstein (D-Calif.) told reporters when asked if she supports filibuster reform. She said she changed her mind on the issue after watching as a bipartisan deal to let President Barack Obama's nominees get votes, struck over the summer, went nowhere.

"We had a meeting in the Old Senate Chamber and everybody had an opportunity ... to really express themselves," Feinstein said of the summer meeting. "I thought it was going to bring about a new day. The new day lasted one week, and then we're back to the usual politics."

She called it "unconscionable" for a president not to be able to have his cabinet team and judicial appointees get votes. She specifically singled out Republicans' treatment of Obama's three nominees to the D.C. Circuit Court of Appeals. All three have been filibustered in the past few weeks. In total, there are now 21 nominees either currently being filibustered or who were filibustered and ultimately withdrew.

"This kind of behavior usually happens in the last six months of a president's tenure," Feinstein said. "But not now."

Neither Boxer nor Feinstein could say whether they thought Democrats had the 51 votes needed to invoke the so-called nuclear option, or the use of archaic Senate procedures to change the rules to strip the minority party of its ability to filibuster nominees. But both said the level of frustration among Democrats is at peak levels right now.

The fact that GOP senators were responsible for filibustering all three of Obama's D.C. Circuit nominees, all of whom were qualified and non-controversial, has "galvanized" Democrats to make changes, Boxer said.

Feinstein added, "If ever there's evidence for [a rules change], it is now."

Senate Democratic leaders still haven't said what they plan to do next. Majority Leader Harry Reid (D-Nev.) continues to keep his cards close, saying something needs to change, but stopping short of offering a concrete proposal. One plan under consideration would strip Republicans of their power to filibuster executive and judicial nominees, but not Supreme Court nominees. But Democratic aides emphasized that nothing is settled yet.

"I'm at the point where we need to do something to allow government to function," Reid told reporters Tuesday. "I'm considering looking at the rules."

Plenty of Democrats have been calling for filibuster reform for months, even years. But their talk hasn't turned into much action. Some Democrats bristled when asked if they thought their party had enough spine to follow through on a rules change.

"That's an interesting suggestion," Sen. Chris Coons (D-Del.) replied, with slight agitation. "The only reason it didn't happen before was an agreement was reached with Republicans. We've apparently reached the limit of that agreement," he added. "It's time to changes the rules for nominees."

"I'm in favor of changing filibuster rules for everything," said Sen. Tom Harkin (D-Iowa), adding that he would be "ecstatic" if Democrats revamped filibuster rules before he retires next year. "I've been wanting to change the rules for 17 years."

Sen. Joe Manchin (D-W.Va.) said he's "open" to the idea of filibuster reform for nominees, saying he sympathizes with Obama on the issue, given his own experience as a governor and an executive. "You have to get your team together," Manchin said. Asked why he thinks some of his colleagues remain reluctant to support changes, he shrugged.

"The easiest vote up here is the status quo and to vote 'no' on everything, I guess," he said. "But you've got to have movement."

At least one Democrat is still firmly opposed to using the nuclear option. Sen. Carl Levin (D-Mich.) said he's fine with a rules change, but only through standard procedure -- with a two-thirds vote, not a simple majority.

"I don't favor using the nuclear option, which violates the rules, to change the rules," Levin said. "I think the complications are so severe for a whole lot of causes."

Meanwhile, two other Democrats, Sens. Max Baucus (Mont.) and Claire McCaskill (Mo.), said they had no comment on the matter and walked away.

But asked if the recent filibusters of Obama's D.C. Circuit nominees have worn down her support for preserving the current rules, McCaskill suggested they have.

"A lot of things wear on me around here," she said over her shoulder. "That's certainly one of them."

Sabrina Siddiqui contributed reporting.

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  • The Numbers

    The House has 233 Republicans and 200 Democrats. Each party should pick up one more seat when two vacancies are filled. Going into the election, the GOP edge was 242-193. Senate Democrats will have a caucus of 55, including two independents, Angus King of Maine and Bernie Sanders of Vermont. Republicans have 45. That's a pickup of two seats for Democrats. <em>(Text <a href="http://www.huffingtonpost.com/huff-wires/20130103/us-new-congress-glance/">via the Associated Press</a>)</em>

  • Women

    The House will have 79 women, including 60 Democrats. At the end of the last session, there were 50 Democratic women and 24 Republican women. The new Senate will have 20 women members, an increase of three. That consists of 16 Democrats and four Republicans. The last Senate had 12 Democratic women and five Republicans. (Text <a href="http://www.huffingtonpost.com/huff-wires/20130103/us-new-congress-glance/">via the Associated Press</a>)

  • Freshmen

    With two vacancies to be filled, the House has 82 freshmen; 47 Democrats and 35 Republicans. As of the end of the last session, 87 of 103 freshmen were Republicans. The Senate will include 14 new faces, with nine Democrats and the independent King. Five are women. New senators include Brian Schatz, who was sworn in on Dec. 27 to fill the seat of the late Hawaii Democrat Daniel Inouye. (Text <a href="http://www.huffingtonpost.com/huff-wires/20130103/us-new-congress-glance/">via the Associated Press</a>) <em>(Pictured at left: Incoming House freshmen of the 113th Congress pose for a group photo on the East steps of the Capitol in Washington, Thursday, Nov. 15, 2012. AP Photo/Susan Walsh)</em>

  • African Americans

    The House will have 40 African-Americans, all Democrats. The number of Democrats is unchanged, although two Republicans will be gone: Allen West, R-Fla., lost his re-election bid, and Tim Scott, R-S.C., was appointed to fill the Senate seat of Jim DeMint, R-S.C., who is retiring. Scott will be the first black lawmaker in the Senate since Roland Burris, who retired in 2010 after filling the Illinois Senate seat of Barack Obama for almost two years. (Text <a href="http://www.huffingtonpost.com/huff-wires/20130103/us-new-congress-glance/">via the Associated Press</a>) <em>(Pictured at left: Rep. Tim Scott, R-S.C., who was appointed by South Carolina Gov. Nikki Haley to replace outgoing Sen. Jim DeMint, R-S.C., walks out of the Republican policy luncheon on Capitol Hill in Washington, Tuesday, Dec. 18, 2012. AP Photo/Susan Walsh)</em>

  • Hispanics

    The new House will have 33 Hispanics, with 25 Democrats and eight Republicans. That's up slightly from last year. The Senate will have three Hispanics: Democrat Robert Menendez of New Jersey, Republican Marco Rubio of Florida and Republican freshman Ted Cruz of Texas. (Text <a href="http://www.huffingtonpost.com/huff-wires/20130103/us-new-congress-glance/">via the Associated Press</a>) <em>(Pictured at left: Rep.-elect Joaquin Castro, D-Texas, speaks with members of the media after a news conference with newly elected Democratic House members on Capitol Hill in Washington, Tuesday, Nov. 13, 2012. AP Photo/Pablo Martinez Monsivais)</em>

  • Other Minorities

    The new House will have nine Asian Americans, all Democrats. There are two American Indians: Tom Cole, R-Okla., and Ben Lujan, D-N.M. (Text <a href="http://www.huffingtonpost.com/huff-wires/20130103/us-new-congress-glance/">via the Associated Press</a>) <em>(Pictured at left: Sen.-elect, current Rep. Mazie Hirono, D-Hawaii, and her husband, Leighton Oshima ride the Senate Subway on Capitol Hill in Washington, Tuesday, Nov. 13, 2012. AP Photo/Harry Hamburg)</em>

  • Other Facts

    According to CQ Roll Call newspaper, the average age of House members in the 113th Congress is 57; the average age of senators is 62. It estimates that the House will include some 277 Protestants and Catholics, 22 Jews, two Muslims and two Buddhists. The Senate will have 80 Protestants and Catholics and 10 Jews. The House will have its first Hindu, Rep.Tulsi Gabbard, D-Hawaii. Senate freshman Mazie Hirono, also of Hawaii, will be the Senate's only Buddhist and its first Asian American woman. Also for the first time, white men will be a minority among House Democrats. (Text <a href="http://www.huffingtonpost.com/huff-wires/20130103/us-new-congress-glance/">via the Associated Press</a>) <em>Pictured at left: Rep.-elect Tulsi Gabbard, D-Hawaii is seen on stage during a news conference with newly elected Democratic House members, on Capitol Hill in Washington, Tuesday, Nov. 13, 2012. AP Photo/Pablo Martinez Monsivais)</em>