An analysis of Federal Election Commission records, by TIME, which was published on 23 October 2015, showed that the 2012 donors to Romney's campaign were already donating more to Hillary Clinton's 2016 campaign than they had been donating to any one of the 2016 campaigns of (listed here in declining order below Clinton) Lindsey Graham, Rand Paul, Carly Fiorina, Chris Christie, Rick Perry, Mike Huckabee, Donald Trump, Bobby Jindal, Rick Santorum, George Pataki, or Jim Gilmore. Those major Romney donors also gave a little to two Democrats (other than to Hillary — who, as mentioned, received a lot of donations from these Republican donors): Martin O'Malley, Jim Web, and Lawrence Lessig. (Romney's donors gave nothing to Bernie Sanders, and nothing to Elizabeth Warren. They don't want either of those people to become President.)
In ascending order above Clinton, Romney's donors were donating to: John Kasich, Scott Walker, Ben Carson, Marco Rubio, Ted Cruz, and Jeb Bush. The top trio — of Bush, Cruz, and Rubio — together, received around 60% of all the money donated for the 2016 race by the people who had funded Mitt Romney's 2012 drive for the White House.
So: the Democrat Hillary Clinton scored above 14 candidates, and below 6 candidates. She was below 6 Republican candidates, and she was above 11 Republican candidates (Lindsey Graham, Rand Paul, Carly Fiorina, Chris Christie, Rick Perry, Mike Huckabee, Donald Trump, Bobby Jindal, Rick Santorum, George Pataki, and Jim Gilmore). The 6 candidates she scored below were: Jeb Bush, Ted Cruz, Marco Rubio, Ben Carson, Scott Walker, and John Kasich.
This means that, in the entire 17-candidate Republican field, she drew more Republican money than did any one of 11 of the Republican candidates, but less Republican money than did any one of 6 of them. So, if she were a Republican (in what would then have been an 18-candidate Republican field for 2016), she would have been the 7th-from-the-top recipient of Romney-donor money.
Therefore, to Republican donors, Hillary Clinton is a more attractive prospect for the U.S. Presidency than was 64% of the then-current 17-member Republican field of candidates.
Another way to view this is that, to Republican donors, a President Hillary Clinton was approximately as attractive a Presidential prospect to lead the nation as was a President Graham, or a President Kasich — and was a more attractive prospective President than a President Lindsey Graham, a President Rand Paul, a President Carly Fiorina, a President Chris Christie, a President Rick Perry, a President Mike Huckabee, a President Donald Trump, a President Bobby Jindal, a President Rick Santorum, or a President George Pataki.
To judge from Clinton's actual record of policy-decisions, and excluding any consideration of her current campaign-rhetoric (which is directed only at Democratic voters), all three of those candidates who were in Clinton's Republican-donor league — Graham, Clinton, and Kasich — would, indeed, be quite similar, from the perceived self-interest standpoint of the major Republican donors.
As to whether any one of those three candidates as President would be substantially worse for Republican donors than would any one of the Republican big-three — Bush, Cruz, and Rubio — a person can only speculate.
However, the main difference between Clinton and the Republican candidates is certainly the rhetoric, not the reality. The reason for that Democratic rhetoric is that Ms. Clinton is competing right now only for Democratic votes, while each one of the Republican candidates is competing right now only for Republican votes.
Hillary Clinton's rhetoric is liberal, but her actual actions in politics have been conservative, except for her nominal support for liberal initiatives that attracted even some Republican support, or else that the Senate vote-counts (at the time when she was in the Senate) indicated in-advance had no real chance of becoming passed into law. In other words: her record was one of rhetoric and pretense on a great many issues, and of meaningful action on only issues that wouldn't embarrass her in a Democratic primary campaign, to attract Democratic voters.
In terms of her actual record in U.S. public office, it's indistinguishable from that of Republican politicians in terms of corruption, and it's indistinguishable from Republican politicians in terms of the policies that she carried out as the U.S. Secretary of State for four years. Her record shows her to be clearly a Republican on both matters (notwithstanding that her rhetoric has been to the exact contrary on both matters).