South Carolina does not have a Republican primary this year, so a couple of groups are urging Republicans to vote in this Saturday's Democratic primary in hopes of giving President Donald Trump an opponent he can beat. Who that is depends on who you ask, but at least one group as a specific target in mind.

The Chicago Tribune reports a group called Trump 229 is urging Republicans to vote for Sen. Bernie Sanders.

Karen Martin, who the Greenville News says has been promoting an effort to get people to vote for Sanders, said a victory by the Vermont senator would hurt Vice President Joe Biden. Biden has said that South Carolina is his firewall given his support among African Americans. But polls in recent days have shown Sanders is within striking distance.

Martin also reportedly said Sanders as the nominee would benefit Trump as it would give voters a clear contrast of ideas, something she believes helps the president.

A separate initiative called "Operation Chaos 2020" is holding an online poll to determine the "craziest liberal looney" that voters should support. As of Tuesday morning, Sen. Elizabeth Warren had 50% of the vote, followed by Andrew Yang (who is no longer running) at 46% and Sanders at 4%.

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Operation Chaos is run by the Conservative Defense Fund. The name Operation Chaos comes from an initiative credited to conservative talk show host Rush Limbaugh in 2008 to get Republicans to vote for Hillary Clinton in the primaries against Barack Obama. The idea was to extend the process as long as possible to hurt the eventual nominee. While the primary fight did go all the way to the convention, there is no way to know how much of that was due to Limbaugh's efforts.

The South Carolina Republican Party canceled its primary this year, choosing to give Trump its delegates by default. South Carolina is an open primary state. Voters can choose to take part in either the Democratic or Republican primary regardless of their affiliation, but they can't vote in both. So Republicans who don't have to vote for their party this year are free to vote in the Democratic primary.

Contrast that with Washington state, where voters who get their primary ballot in the mail have to check whether they are voting in the Democratic or Republican primary.

That is reportedly also part of the reason behind Operation Chaos -- to get the state to go to a closed primary system and end the ability for voters to cross over and affect the other party's primary.