With Donald Trump emerging as the presumptive GOP presidential nominee, Democrat leaders are beginning to launch attacks on the real estate mogul as the 2016 campaign shifts into general election mode.

SEE ALSO: Donald Trump is going to be the GOP nominee and people are freaking out

With Ted Cruz and John Kasich dropping out of the race, Trump is the only GOP candidate left standing and Republican leadership is putting their weight behind him now, like it or not.

.@realDonaldTrump will be presumptive @GOP nominee, we all need to unite and focus on defeating @HillaryClinton #NeverClinton — Reince Priebus (@Reince) May 4, 2016

So on Wednesday, Hillary Clinton, the Democratic front-runner, launched an ad aimed directly at Trump, her first major salvo in the general election campaign. But, in a bit of a twist, the ad uses the words of GOP leaders and fellow GOP candidates against Trump, a nice bit of political handiwork in a time when the GOP is trying to pick up the pieces and unify after a brutal primary campaign.

Watch the ad below.

"President Trump" is a dangerous proposition.



Mitt Romney, Ted Cruz, and Marco Rubio agree.https://t.co/fUkISvgaXC — Hillary Clinton (@HillaryClinton) May 4, 2016

For his part, Trump was fairly quiet Wednesday, using his Twitter account mainly to promote upcoming television appearances while taking time out to call the Democratic primary rigged against Clinton's opponent, Bernie Sanders.

I would rather run against Crooked Hillary Clinton than Bernie Sanders and that will happen because the books are cooked against Bernie! — Donald J. Trump (@realDonaldTrump) May 4, 2016

What a great evening we had. So interesting that Sanders beat Crooked Hillary. The dysfunctional system is totally rigged against him! — Donald J. Trump (@realDonaldTrump) May 4, 2016

Clinton's ad comes on the heels of a series of blistering tweets from Democratic Sen. Elizabeth Warren, who blasted Trump Tuesday night to the delight of her supporters.

.@realDonaldTrump is now the leader of the @GOP. It's real - he is one step away from the White House. — Elizabeth Warren (@elizabethforma) May 4, 2016

Here’s what else is real: @realDonaldTrump has built his campaign on racism, sexism, and xenophobia. — Elizabeth Warren (@elizabethforma) May 4, 2016

Here’s what else is real: @realDonaldTrump has built his campaign on racism, sexism, and xenophobia. — Elizabeth Warren (@elizabethforma) May 4, 2016

There's more enthusiasm for @realDonaldTrump among leaders of the KKK than leaders of the political party he now controls. — Elizabeth Warren (@elizabethforma) May 4, 2016

.@realDonaldTrump incites supporters to violence, praises Putin, and is "cool with being called an authoritarian." — Elizabeth Warren (@elizabethforma) May 4, 2016

.@realDonaldTrump attacks vets like @SenJohnMcCain who were captured & puts our servicemembers at risk by cheerleading illegal torture. — Elizabeth Warren (@elizabethforma) May 4, 2016

And @realDonaldTrump puts out out contradictory & nonsensical national security ideas one expert called "incoherent" & "truly bizarre." — Elizabeth Warren (@elizabethforma) May 4, 2016

What happens next will test the character for all of us – Republican, Democrat, and Independent. — Elizabeth Warren (@elizabethforma) May 4, 2016

It will determine whether we move forward as one nation or splinter at the hands of one man's narcissism and divisiveness. — Elizabeth Warren (@elizabethforma) May 4, 2016

I'm going to fight my heart out to make sure @realDonaldTrump’s toxic stew of hatred & insecurity never reaches the White House. — Elizabeth Warren (@elizabethforma) May 4, 2016

In case you were wondering, Election Day is still 187 days away.

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