Seven-term Democratic Iowa congressman Dave Loebsack endorsed Pete Buttigieg's presidential bid, a boost for the former South Bend, Indiana, mayor with just three weeks until the first-in-the-nation Iowa caucuses.

"Pete offers a new kind of leadership that we desperately need — he's a Midwestern mayor, a veteran, and is from a new generation," Loebsack said Sunday. "Iowans and our country face great challenges like climate change, increasing health care costs, and an economy that isn't working for the majority of Americans. They can't be solved with the same political warfare that is on display in Washington."

Loebsack is the second of the three Democratic Iowa members of Congress to endorse a presidential candidate. Democratic Rep. Abby Finkenauer endorsed former Vice President Joe Biden earlier this month. Rep. Cindy Axne has not made an endorsement in the Democratic presidential primary.

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Buttigieg is at the top of the Democratic presidential field in Iowa with three other candidates. The most recent Des Moines Register poll of likely Iowa Democratic caucusgoers released Friday found him in third place with 16% support, while Vermont Sen. Bernie Sanders led with 20%, Massachusetts Sen. Elizabeth Warren had 17%, and Biden had 16% support.

A strong finish in the first two Democratic nominating contests in Iowa and New Hampshire will be critical for Buttigieg's momentum in the race and to prove viability as a presidential candidate despite never holding national office. According to the RealClearPolitics average of primary polls, he lags in fourth place at 7.5% nationally.

"Pete is the candidate that can heal our divides, restore decency to the presidency, and bring this country together," Loebsack said. "When I introduced Pete to a crowd of more than 1,000 Iowans in Mount Vernon in December, it was clear that his campaign is already inspiring a sense of hope and optimism. With Pete in the Oval Office, I believe our nation will unite and move forward together."

[ Related: Pete Buttigieg surges and Elizabeth Warren crashes in New Hampshire poll]