Sometimes an insult can be the greatest compliment of all — especially when it comes to politics.

To be singled out — and attacked — is a neon sign a politician is powerful enough to pose a threat.

And President Donald Trump's scorching tweet on Tuesday aimed at Senator Kirsten Gillibrand is being viewed in Washington as a sign Gillibrand is a top contender for President in 2020.

Trump's tweet backfires

But if the President's tweet was meant to slow Gillibrand down, it backfired.

President Trump called Gillibrand a "lightweight" and "flunky" who would 'come to my office "begging" for campaign contributions not so long ago (and would do anything for them)."

On Wednesday, Senator Gillibrand told the NBC Today Show Trump's latest tweet was:

"a sexist smear intended to silence me. And I'm not going to be silenced on this issue. I've heard the testimony of many women, numerous accusers, I believe them. And he should resign for that."
Gillibrand, who says Trump was simply a supporter of her first campaign, wasn't the only person to note sexually suggestive overtones in the tweet.

Senator Elizabeth Warren accused the President of trying to "bully, intimidate and slut-shame" Gillibrand.

The editorial board of USA Today opined:

"With his latest tweet, clearly implying that a United States Senator would trade sexual favours for campaign cash, President Trump has shown he is not fit for office."
White House spokeswoman Sarah Huckabee Sanders sharply disagreed:

"I think only if your mind was in the gutter would you have read it that way."

Gillibrand leading #metoo charge

The battle between Trump and Gillibrand comes against the backdrop of the #MeToo movement which has seen a string of powerful men in entertainment, media and politics step down or lose their jobs, and in the wake of the Republican Senate candidate Roy Moore's stinging loss in Alabama to Democrat Doug Jones.

On Capitol Hill, a group of House Democrats has called for an investigation into allegations of sexual misconduct by the President.

In the upper chamber, Senator Gillibrand has led the charge on sexual harassment allegations.

She was among those who called on fellow Democrat Senator Al Franken to step down in the wake of allegations of sexual impropriety. Gillibrand took fire from some over her comments that former President Bill Clinton should have stepped down because of his relationship with a White House Intern.

Now, the Senator says allegations against President Trump — including calls this week from some of the women themselves — must be investigated.

On Today she told NBC's Savannah Guthrie:

"He's a bully and he's been attacking different people across this country since he's been President and since the Women's March, women have stood up, have fought hard, have spoken out about their beliefs. And they've not stopped ... because of it I have hope for this country."
The Senator Majority Leader, Mitch McConnell has sidestepped the issue, telling reporters, "What we're in charge of here is the Senate."

The tweet that started it all

That Gillibrand's star is on the rise is beyond dispute.

Because of how she's handled herself in the wake of a Twitter torpedo from the President of the United States.

And because she was singled out for that tweet in the first place.