(CNN) Democratic leaders are split on how to handle impeachment. House Speaker Nancy Pelosi has called for Democrats to continue investigating President Donald Trump, but has not said an impeachment inquiry should begin. Many of the Democrats running for president are going in a different direction. Led by Sen. Elizabeth Warren of Massachusetts, a number have called for an impeachment inquiry.

Why the difference? It has everything to do with who these Democratic politicians hope to appeal to.

Pelosi's electoral job is to maintain the Democratic House majority. That is, she wants to win the general election, which will be difficult for Republicans to win because Trump is unpopular. The President's approval rating overall is only 43% with voters . It's not any better with independents who don't lean toward either the Democratic or Republican party (i.e. true independents). These true independents are the voters who members in swing districts will need to win.

Pelosi probably fears that talk of impeachment gives Republicans an electoral opening. In our latest CNN poll, 54% of voters nationally do not want to impeach and remove the President from office, while just 41% of them do. And while true independents are against the President, they are against impeaching and removing him from office, too.

Perhaps most worrisome to Pelosi is the intensity factor. If enthusiasm was on the side of Democrats in the 2018 midterm elections, a general election about impeachment could reverse that enthusiasm gap in 2020. Those who are strongly against impeaching and removing the President from office outnumber the strongly for impeaching and removing the President from office crowd by 45% to 36%. This same intensity gap holds true with true independents.

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