WASHINGTON – Former President Barack Obama on Monday announced endorsements of another 260 Democratic candidates in November midterm elections, bringing his total number of endorsements this year to about 350.

Obama is focusing on close races for governor, U.S. Senate, U.S. House and state legislatures in which he believes his support will make a meaningful difference. He said the candidates "make up a movement of citizens who are younger, more diverse, more female than ever before."

Included in this wave of endorsements is a host of candidates who are breaking boundaries. Among them:

• Rep. Kyrsten Sinema, who is running a competitive race against GOP Rep. Martha McSally to become Arizona's first woman elected to the U.S. Senate.

• Jahana Hayes, who is likely to be Connecticut's first black woman – along with the state's first black Democrat – elected to Congress.

• Tallahassee Mayor Andrew Gillum, the first African-American major party nominee for governor in Florida.

• Boston City Councilor Ayanna Pressley, who is poised to become the first black woman elected to Congress from Massachusetts.

• New York activist Alexandria Ocasio-Cortez, who at 28 could be the youngest woman elected to Congress.

• Vermont Democrat Christine Hallquist, the nation’s first openly transgender candidate nominated for governor by a major party.

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Obama on Monday also backed two of the 10 Senate Democrats who are running for re-election in states that voted for Trump – Sens. Tammy Baldwin of Wisconsin and Bill Nelson of Florida. He appeared previously at a fundraiser for Sen. Claire McCaskill of Missouri.

“They’re Americans who aren’t just running against something, but for something," Obama said in his statement. "They’re running to expand opportunity and restore the honor and compassion that should be the essence of public service."

The endorsements build on an initial round of 81 midterm endorsements he announced in August and several campaign appearances over the last month.

Last month, Obama unleashed a blistering attack on President Donald Trump and Republicans and called on Americans to get to the ballot box in November to "restore some semblance of sanity to our politics."