Source: Newspapers run IDENTICAL letters slamming Trump’s Supreme Court pick | Daily Mail Online
At least one of the signatories to the letter says she never sent the letter and suggests that her name was lifted off a petition.
This was an astro-turf propaganda operation, flooding the world with a message that is made to look like it comes “from the people” (grass roots) when in fact, it was manufactured by an organization or public relations agency working on behalf of an organization.
We covered use of “astroturf” operations in 3 prior posts.
Basically you should assume that 100% of what you see in media or social media (or online forums and review sites!) is fake.

In 2004 the liberal group MoveOn.org launched a website tool that generated editorial letters for its members promoting the Michael Moore film ‘Fahrenheit 911.’ All it required was a name, hometown and ZIP code.

The program provided users with sample sentences and a salt-to-taste text editor. Many left the stock message the way it was and clicked ‘send.’

The USC Annenberg School for Communication and Journalism’s Online Journalism Review reported that the Republican National Committee had the technique down a year earlier.

Using a website called ‘GOP Team Leader,’ the party offered ‘points’– redeemable for merchandise – when their letters were actually published.