The U.S. Senate race in Arizona is heating up, with Democrats increasingly optimistic that Richard Carmona can beat Rep. Jeff Flake (R-Ariz.). The latest evidence is national Democrats investing resources in the race.

The Democratic Senatorial Campaign Committee has reserved $526,000 in TV airtime, according to a Democratic source who tracks campaign advertising. The ads will run from Oct. 2 to Oct. 8.

It's the national committee's first ad campaign in Arizona.

Politico reported last week that the Tea Party group FreedomWorks is sending additional staff and resources to Arizona to help Flake, "another sign his race against Carmona is tightening in the traditionally red state."

Real Clear Politics also recently changed its assessment of the Arizona Senate race as a "toss-up," after it originally leaned Republican.

HuffPost Pollster, in its average of polls, still has Flake leading by about three percentage points, although the race has significantly tightened.

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  • Virginia

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  • Missouri

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  • Massachusetts

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  • Ohio

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  • Nevada

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  • Montana

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  • Florida

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  • Michigan

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  • Wisconsin

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  • New Jersey

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  • Pennsylvania

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  • Arizona

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  • New Mexico

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