Sen. Barbara BoxerBarbara BoxerTrump riles Dems with pick for powerful EPA job Pelosi's chief of staff stepping down Time is now to address infrastructure needs MORE's (D-Calif.) campaign reached out to Republican rival Carly Fiorina for help this week -- but not on purpose.

Boxer's fundraising team sent an invite to Fiorina's personal e-mail asking her to attend the campaign's May 25 event with President Barack ObamaBarack Hussein ObamaGOP rep: North Korea wants Iran-type nuclear deal Dems fear lasting damage from Clinton-Sanders fight Iran's president warns US will pay 'high cost' if Trump ditches nuclear deal MORE in San Francisco.

The invitation states, "With the June Primary upon us, Sen. Boxer needs to be prepared to face the 'fight of her life.' Your support is critical."

It offers prospective donors who raise $20,000 the chance of attending a 'private clutch,' presumably with Boxer and Obama.

Fiorina won't be able to make it, according to campaign spokeswoman Amy Thoma. "Sadly, she'll have to decline as she'll be out giving Boxer the [above] referenced 'fight of her life.'"

The Boxer camp confirmed the e-mail was authentic but noted it went to "thousands" of people.

Fiorina wasn't the only Republican on the list -- her campaign manager, Marty Wilson, got the invite last week.