Nevada Democrat Dina Titus threw her support behind Joe Biden on Monday, scoring the former vice president his first endorsement from a sitting member of Congress in any of the nation's early nominating contests.

"I can't tell you how happy I am to have Representative Titus in my corner for the fight we have ahead of us," the former vice president told reporters on a phone call later in the day. "We've been friends for a long time."

Nevada votes third among the early contests, after Iowa and New Hampshire, and is a crucial test of support among the Western state's booming Latino, Asian American, and labor union constituencies. Recent polls show Biden with a commanding lead in the state, ahead of Senators Bernie Sanders and Elizabeth Warren.

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While the backing will not lend Biden the political muscle of Nevada's coveted labor groups or activists, who have yet to endorse, Titus says she is already organizing events in her majority-minority district to help grow Biden's support in a key battleground: the urban core of Las Vegas.

"I represent the most ethnically diverse district in the state and there's a large Hispanic population here, mostly from Central America and Mexico. If I thought there was any problem, or my constituents did, with your record in that community, I wouldn't be endorsing you," Titus said of Biden on the call.

Titus has championed liberal causes during her time in the House, eagerly embracing Nevada's marijuana legalization, becoming the first of the state's congressional delegation to call for impeachment, and cosponsoring Medicare for All legislation.

"I'm a proud progressive," Titus told CBS News later Monday, asked about the apparent gap between her positions and the former vice president.

"When the vice president talks about the public option, I support that. And I see that as the first step towards getting to universal coverage. He's done it before, so I think he has more success in moving us down that line than the other candidates," added Titus.

Many of Nevada's most prominent Democrats — including former Senate Majority Leader Harry Reid and both of the state's current senators — have pledged not to pick favorites before February 22nd.

Of the state's congressional delegation, only Representative Steven Horsford has expressed openness to making an endorsement ahead of the caucuses.

Titus, who endorsed Hillary Clinton before both the state's 2008 and 2016 caucuses, had speculated as early as last year that she might endorse the former vice president. However, Titus claims she had yet to make up her mind earlier this month when she introduced both Biden and Sanders at events in her district.

"After the last debate and the poll numbers that went up after the last debate, and just thinking it through, I decided that there's no point in waiting any longer. He's the right person at the right time," the congresswoman said.