WASHINGTON – Sen. Bernie Sanders announced Thursday that he will campaign in nine battleground states this month to try to elect Democrats in congressional, gubernatorial and state legislature races from California to South Carolina.

Sanders, the 77-year-old Vermont independent who ran for president as a Democrat in 2016, said he will support "progressive" candidates during his nine-day tour across the country. However, not all the Democrats that Sanders is helping are liberal enough to be considered progressive.

Some of them, like Rep. Jacky Rosen, who is challenging Republican Sen. Dean Heller in Nevada, are viewed as traditional, mainstream Democrats. Former Senate Majority Leader Harry Reid, D-Nev., who is not a left-wing darling, helped convince Rosen to run.

Sanders, in an email to supporters Thursday, said the Nov. 6 election is "a pivotal moment in American history."

"Do we continue with a one-party, right-wing government in Washington led by a pathological liar with strong authoritarian tendencies?" Sanders wrote, referring to President Donald Trump. "Or, do we stand up to Trump and fight for an agenda that represents all Americans, and not just the 1%?"

Sanders, who describes himself as a democratic socialist, will campaign while the Senate is in recess. He will stump for candidates in Arizona, California, Colorado, Indiana, Iowa, Michigan, Nevada, South Carolina and Wisconsin.

It is Sanders' longest campaign stretch since he ran for president two years ago. He has not decided whether to make another bid for the White House in 2020.

Here's the breakdown of where he's going:

Sanders' tour will begin Oct. 19 in Bloomington, Indiana, where he will rally support for Democratic congressional candidate Liz Watson, who is challenging Republican Rep. Trey Hollingsworth.

in Bloomington, Indiana, where he will rally support for Democratic congressional candidate Liz Watson, who is challenging Republican Rep. Trey Hollingsworth. He will also appear on Oct. 19 in Ann Arbor, Michigan, to campaign for gubernatorial candidate Gretchen Whitmer, who is running against Republican Bill Schuette. Schuette has been endorsed by Trump.

in Ann Arbor, Michigan, to campaign for gubernatorial candidate Gretchen Whitmer, who is running against Republican Bill Schuette. Schuette has been endorsed by Trump. Sanders will help Our Revolution SC rally support on Oct. 20 in Columbia, South Carolina, for Democratic gubernatorial candidate James Smith. While Smith welcomes Sanders' help, some Democratic leaders have said they believe the senator could do more harm than good in the conservative state. Smith is running against Republican Gov. Henry McMaster.

in Columbia, South Carolina, for Democratic gubernatorial candidate James Smith. While Smith welcomes Sanders' help, some Democratic leaders have said they believe the senator could do more harm than good in the conservative state. Smith is running against Republican Gov. Henry McMaster. The senator will campaign Oct. 20 in Sioux City, Iowa, and Oct. 21 in Fort Dodge and Ames, Iowa, for J.D. Scholten, the Democrat challenging Rep. Steve King, who is known for his extremely conservative stands on immigration.

in Sioux City, Iowa, and in Fort Dodge and Ames, Iowa, for J.D. Scholten, the Democrat challenging Rep. Steve King, who is known for his extremely conservative stands on immigration. He will campaign for Democratic Sen. Tammy Baldwin in Milwaukee, Wisconsin, on Oct. 22.

He will rally in Phoenix and Tucson, Arizona, on Oct. 23 for gubernatorial candidate David Garcia, who is challenging Republican Gov. Doug Ducey.

for gubernatorial candidate David Garcia, who is challenging Republican Gov. Doug Ducey. Additionally, he'll rally for Democratic Rep. Jared Polis in Boulder and Ft. Collins, Colorado, on Oct. 24 .

. Sanders will campaign for Rosen in Las Vegas and Reno, Nevada on Oct. 25 .

. In California, Sanders will support Democratic congressional candidates Ammar Campa-Najjar and Mike Levin on Oct. 26 in San Diego. Campa-Najjar is challenging embattled Republican Rep. Duncan Hunter, who has been indicted on fraud and corruption charges. Hunter has declared his innocence. Levin is running against Republican Diane Harkey for the open seat now held by retiring GOP Rep. Darrell Issa. Sanders will also campaign for Democratic Rep. Barbara Lee In Oakland on Oct. 27.

Sanders said his goal is to work with the candidates to "do everything I can to get working people and young people involved in the political process and to the polls."

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