One of the most important moments in Rep. Kevin McCarthy's (R-Calif.) political career came in late-September 2015, as the then-House majority leader appeared poised to become Speaker of the House. The California Republican's efforts were derailed, however, when he made the mistake of accidentally telling the truth.

McCarthy appeared on Fox News and acknowledged a fact that everyone knew, but which Republicans weren't supposed to admit out loud: the GOP's taxpayer-financed Benghazi committee was all about the Republicans' "strategy to fight and win" against Hillary Clinton. Or put another way, it was not a sincere effort to investigate an attack that left four Americans dead.

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The congressman's bid to become Speaker collapsed soon after.

More than four years later, on the other side of Capitol Hill, senators spent much of their afternoon listening to Donald Trump's lawyers during a Senate impeachment trial, which included lengthy attacks against presidential hopeful Joe Biden. A Washington Post analysis described Team Trump's attacks against the Delaware Democrat as "weak," "sloppy," and "wildly misleading." Pointing to one particular line of attack launched by Pam Bondi, the analysis added that the Florida Republican "shared untrue claims as though they'd never been assessed for veracity at all."

And why, pray tell, would the president's lawyers try to defend their client by going after one of his rivals with bogus smears? One Senate Republican offered a possible explanation.

Sen. Joni Ernst (R-Iowa) says she'll be watching the upcoming Iowa caucus results to see if Democratic voters sour on former Vice President Joe Biden, a 2020 presidential contender, after the arguments presented by President Donald Trump's impeachment defense team on Monday. "I'm really interested to see how this discussion today informs and influences the Iowa caucus voters. Will they be supporting Vice President Biden at this point?" Ernst, a member of GOP leadership, asked at a press conference Monday.

As former Sen. Claire McCaskill (D-Mo.), an MSNBC political analyst, noted on Twitter soon after, "Umm. I think Joni just gave up the game."

Quite right. Like Kevin McCarthy in 2015, Joni Ernst said the quiet part loud yesterday, suggesting Team Trump's attacks against Biden were less about presenting a legal defense during an impeachment trial, and more about influencing the outcome of an election.

Not surprisingly, the Biden campaign took note, and the former vice president's official Twitter account said last night, "Iowa caucus-goers take note. Joni Ernst just spilled the beans."

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